1000 resultados para 93-605


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完成了19F+93Nb重离子耗散碰撞激发函数的两次独立测量.束流19F8+的入射能量100—108MeV,能量步长250keV;两次测量中分别使用了厚度为70和71μg/cm2的93Nb靶,其它宏观实验条件(例如,入射能量及能量步长,探测器及其探测角度,加速器、电子学以及数据获取系统的参数选取等等)则保持完全相同.实验结果表明,两次测量所得到的耗散产物截面的激发函数的不平滑结构具有不可重复性.这一实验结果支持了最近提出的理论预言:“在复杂量子碰撞中存在对初始条件的极端敏感性与混沌运动.”

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本文简要叙述了快重离子在固体材料,特别是聚合物材料中引起的强电子激发效应研究的基本理论、发展历史和研究现状。描述了在兰州重离子加速器上完成的25 MeV/u 86Kr离子辐照叠层聚对苯二甲酸乙二醇酯膜(PET)和聚碳酸酯(PC)膜的实验及结果分析。应用傅立叶红外变换光谱(FT-IR)及X-射线衍射分析(XRD)方法研究了在不同电子能损及不同注量辐照条件下,高能Kr离子在聚合物PET和PC潜径迹中引起的的损伤效应。结果表明:高能Kr离子在聚合物PET、PC膜引起的损伤主要是由于辐照引起的断键及键的重组产生的官能团的降解及非晶化过程,损伤截面存在电子能损阈值,且与官能团的结构有关。 对PET的傅立叶红外变换光谱分析结果给出,电子能损为7.25 keV/nm时,对应官能团吸收峰794 cm-1, 849 cm-1, 1021 cm-1, 1341 cm-1, 1410 cm-1, 1505 cm-1,的损伤截面半径分别为:3.63 nm, 4.70 nm, 4.58 nm, 3.54 nm, 5.17 nm, 5.32 nm。X-射线衍射分析结果表明,PET的非晶化转变截面随离子注量和电子能损的增大而增加,(100)衍射峰的相对强度I/I0随离子注量的增加而指数衰减,对应电子能损为6.62, 6.93, 7.25 keV/nm,其相应的非晶化半径分别为4.86, 5.64, 6.77 nm。 对PC的傅立叶红外变换光谱分析表明,当电子能损比较小,大多数官能团的红外吸收无明显变化,直到当辐照注量为2×1012 ions/cm2 且电子能损比较大时,其绝对吸收强度才发生明显的改变。电子能损为6.37 keV/nm 时,对应官能团吸收峰为519 cm-1, 605 cm-1, 724 cm-1, 1014 cm-1,其损伤截面分别为:13.12, 45.40, 50.21, 56.28 nm2

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Ireland experienced two critical junctures when its economic survival was threatened: 1958/9 and 1986/7. Common to both crises was the supplanting of long established practices, that had become an integral part of the political culture of the state, by new ideas that ensured eventual economic recovery. In their adoption and implementation these ideas also fundamentally changed the institutions of state – how politics was done, how it was organised and regulated. The end result was the transformation of the Irish state. The main hypothesis of this thesis is that at those critical junctures the political and administrative elites who enabled economic recovery were not just making pragmatic decisions, their actions were influenced by ideas. Systematic content analysis of the published works of the main ideational actors, together with primary interviews with those actors still alive, reveals how their ideas were formed, what influenced them, and how they set about implementing their ideas. As the hypothesis assumes institutional change over time historical institutionalism serves as the theoretical framework. Central to this theory is the idea that choices made when a policy is being initiated or an institution formed will have a continuing influence long into the future. Institutions of state become ‘path dependent’ and impervious to change – the forces of inertia take over. That path dependency is broken at critical junctures. At those moments ideas play a major role as they offer a set of ready-made solutions. Historical institutionalism serves as a robust framework for proving that in the transformation of Ireland the role of ideas in punctuating institutional path dependency at critical junctures was central.

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Hyperadrenocorticism is a rare endocrine disease in the cat; it is characterized by elevated blood cortisol level that generates numerous clinical signs including hyperglycemia, polyuria, polydipsia, polyphagia and skin diseases. The average age of onset is around 10 years. This disease usually occurs link with other endocrine disorders such as diabetes mellitus.The disease can be produced by functional alteration of the pituitary gland or the adrenal. A case report, with differential diagnosis and review of the literature, is presented.

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This single center study is the largest series of renal transplant recipients and donors screened for the commonest prothrombotic genotypes. A total of 562 transplant recipients and 457 kidney donors were genotyped for the factor V Leiden and prothrombin G20210A mutations. The prevalence of heterozygous factor V Leiden was 3.4% and 2.6% and prothrombin G20210A was 2.0% and 1.1% in recipients and donors, respectively, similar frequencies to that of the general U.K. population. The 30-day and 1-year graft survival rates in recipients with thrombophilic mutations were 93% and 93%, compared with 88% and 82% in patients without these mutations (log-rank P =0.34). Thrombophilia in recipients (odds ratio 0.55; confidence interval 0.06-2.29; P =0.56) or in donors (odds ratio 1.53; confidence interval 0.27-5.74; P =0.46) did not correlate with graft loss at 30 days after transplantation. In contrast to recent reports, this study did not demonstrate an association between thrombophilia and renal allograft loss, and routine screening is not recommended.

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The dielectric properties of Au/[93%Pb(Mg1/3Nb2/3)O-3-7%PbTiO3] (PMN-PT)/(La0.5Sr0.5)CoO3/MgO thin-film capacitor heterostructures, made using pulsed laser deposition, have been investigated, with particular emphasis on the changes in response associated with increasing the magnitude of the ac measuring field. It was found that increasing the ac field caused a change in the frequency spectrum of relaxators, increasing the speed of response of "slow" relaxators, with an associated decrease in the freezing temperature (T-f) of the relaxor system; in addition, other characteristic parameters relating to polar relaxation (activation energy E-a and attempt frequency 1/tau(0)), described by fitting of the dielectric response to a Vogel-Fulcher expression, were found to change continuously as ac field levels were increased.

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Freedom to provide services - Nationals of a non-member country - Posted Workers

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Failure to fulfil obligations - Freedom to provide services - Tourist guides - Professional qualification required by national rule - Discrimination - Museum admission

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When James Joyce made two of his characters in ‘‘Portrait of an Artist as a Young Man’’ refer approvingly to ‘‘Vexilla regis prodeunt’’ he was following in the footsteps of a long line of the Latin text’s admirers. Since Anglo-Saxon times English audiences had clearly appreciated the sonorous majesty of this processional hymn, largely because of the solemnity and craft with which it celebrated the nature of Christ’s martial triumph and sacrifice. This article offers a snapshot of different kinds of English appetite for Venantius Fortunatus’ famous religious song for the first thousand years of its existence, from the Anglo-Saxon period through to the mid sixteenth century.

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BACKGROUND: We report on a young female, who presents with a severe speech and language disorder and a balanced de novo complex chromosomal rearrangement, likely to have resulted from a chromosome 7 pericentromeric inversion, followed by a chromosome 7 and 11 translocation. RESULTS: Using molecular cytogenetics, we mapped the four breakpoints to 7p21.1-15.3 (chromosome position: 20,954,043-21,001,537, hg19), 7q31 (chromosome position: 114,528,369-114,556,605, hg19), 7q21.3 (chromosome position: 93,884,065-93,933,453, hg19) and 11p12 (chromosome position: 38,601,145-38,621,572, hg19). These regions contain only non-coding transcripts (ENSG00000232790 on 7p21.1 and TCONS_00013886, TCONS_00013887, TCONS_00014353, TCONS_00013888 on 7q21) indicating that no coding sequences are directly disrupted. The breakpoint on 7q31 mapped 200 kb downstream of FOXP2, a well-known language gene. No splice site or non-synonymous coding variants were found in the FOXP2 coding sequence. We were unable to detect any changes in the expression level of FOXP2 in fibroblast cells derived from the proband, although this may be the result of the low expression level of FOXP2 in these cells. CONCLUSIONS: We conclude that the phenotype observed in this patient either arises from a subtle change in FOXP2 regulation due to the disruption of a downstream element controlling its expression, or from the direct disruption of non-coding RNAs.

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OBJECTIVE: To evaluate the pertinence of prenatal diagnosis in cases of congenital uropathy. STUDY DESIGN: Retrospective evaluation over a period of 6.5 years. METHOD: 93 cases were involved in the comparison of prenatal ultrasonographic diagnosis with neonatal findings, autopsy results, and follow-up data. RESULTS: 33 fetuses had renal parenchymal lesions, 44 had excretory system lesions, and 6 had bladder and/or urethral lesions. Seventy-three pregnancies lead to live births. Eighteen terminations of pregnancy were performed on the parents' request for extremely severe malformations. Two intrauterine deaths were observed, and two infants died in the postnatal period. Prenatal diagnosis was obtained at an average of 27 weeks gestation. Diagnostic concordance was excellent in 82% and partial in 12% of cases with renal parenchymal lesions; the false-positive rate was 6%. For excretory system lesions, concordance was excellent in 87% and partial in 7.4% of cases, with a false-positive rate of 5.6%. Finally, concordance was excellent in 100% of cases of bladder and/or urethral lesions. The overall rate of total concordance was 86%. Partial concordance cases consisted of malformations different from those previously diagnosed, but prenatal diagnosis nevertheless lead to further investigations in the neonatal period and to proper management. The false-positive diagnoses (5.4%) never lead to termination of pregnancy. CONCLUSION: Prenatal diagnosis of congenital uropathy is effective. A third-trimester ultrasonographic examination is necessary to ensure proper neonatal management, considering that the majority of cases are diagnosed at this gestational age.